Seattle Seahawks cornerback Tharold Simon (27) hits Denver Broncos tight end Gerell Robinson (89) across his face in the third quarter of a preseason game at Sports Authority Field at Mile High. The Broncos defeated the Seahawks 21-16. / Ron Chenoy, USA TODAY Sports

by Lindsay H. Jones, USA TODAY Sports

by Lindsay H. Jones, USA TODAY Sports

DENVER â?? Go ahead and blame Seattle's Legion of Boom for what will surely be a rash of flags this season, for defensive holding and illegal contact and pass interference, but the men who precipitated that rule are going to take it as a compliment.

Indeed, Seattle's scary secondary has changed the NFL with their bump-you, grab-you, hold-you, smash-you style of defense that they rode to a Super Bowl title last year.

But here's the rub: the NFL's rule makers might not be able to catch up with the Legion of Boom.

"We understand where the game is going, and we adapted to the rule change," Seattle safety Earl Thomas told USA TODAY Sports.

Thomas sat at his locker at Sports Authority Field at Mile High late Thursday night, still in his full uniform as he lamented a sloppy 21-16 loss to the Denver Broncos. The game, nearly four hours long, saw 25 total assessed penalties, split nearly evenly between the two teams.

Yet none of those 13 flags called on the Seahawks were for an illegal play on a wide receiver, and it wasn't because the referees weren't looking for it. Thomas and his secondary teammates have grown used to hearing opponents complain to the referees about their handsy play. With an added emphasis from officials this preseason on downfield contact, the Seahawks were expecting more intense scrutiny.

"We knew that the emphasis would be on making sure they called penalties, to let us know they're not playing this year," Thomas said.

So Thomas and Kam Chancellor, who sat out of Thursday night's opener as he continues recovering from offseason hip surgery, and cornerbacks Richard Sherman and Byron Maxwell attacked the rule change like they would any group of wide receivers.

Aggressively.

"You just practice it, and it becomes second nature. We've been in practice, trying to keep our hands clean in one-on-ones," Thomas said. "Every chance we get, we want to help this team in a positive way. We definitely don't want to penalize this team."

It's a lesson the rest of the league will have to learn as well, starting, perhaps, with the Denver Broncos.

Four Denver starters were flagged Thursday night for costly passing-game penalties â?? defensive holding on safety T.J. Ward on the Broncos' second defensive snap; followed by a defensive holding call on corner Aqib Talib, illegal contact on middle linebacker Nate Irving and pass interference on weakside linebacker Danny Trevathan, all on the same drive in the second quarter. That drive ended with a Seahawks' touchdown.

"That gave them a lot of field position and gave up a lot of yards for us," Irving said.

Talib said the Broncos won't fret about the yellow flags when they return to training camp this week, and it won't change the way the Broncos practice. So don't expect to all of a sudden see the Broncos' defensive backs wearing kickboxing gloves at practice to prevent themselves from grabbing.

"I got some good hands on guys, they didn't call everything. They got one of them. It is what is," Talib said. "You just play football. If you get a flag, that's illegal, and we don't practice illegal stuff."

Thomas and his Seattle teammates seem to feel sure the Legion of Boom Rule will stick, even if it's too early in the preseason to see just how it is panning out across the league. Across the loading dock in the Broncos' locker room, Ward wasn't so sure.

"We'll see how it goes, how well it works," Ward said. "I think preseason is all about trial and error, whether it's the refs, teams, players. It's all about trying things to see how it works. We'll see what happens when it comes to the regular season."